Happy Sunday everyone, So yesterday I was able to get out and put some time on my used mk1, what a machine!, just a one hole gun at 40 yds with 44 jsbs, averaging 865 fps for 22 shots before it goes off reg and 3 sd. Now to the question, it's got the shorter 300cc air tube, i see that fx has a 100mm longer air tube extension but no mention that it fits the b/cat .30, has anybody tried using this to increase the shot count, any suggestions.